Piston-rod packing.



PATENTED MAY 9, 1905.

A. W. UHESTBRTON.

PISTON ROD PACKING.

APPLIUATION FILED JAN. 10, 1905.

TINTTE STATES Patented May 9, 1905.

PATENT EETEE.

PISTON-ROD PACKING.

SPECIFICATION forming part of Letters Patent No. 789,141, dated May 9, 1905.

Application filed January 10, 1905. Serial No. 240,403.

To all whom it may concern:

Be it known that I, ARTHUR W. CHESTER- TON, a citizen of the United States, residing at Boston, in the county of Suffolk and Commonwealth of Massachusetts, have invented certain Improvements in Piston-Packings, of which the following is a specification.

This invention relates to that form of packing which is commercially known as seetional packing; and it consists in a packing made up of four strips of material triangular or wedge shape in cross-section, with their apexes toward the center. One strip, to constitute the bearing-surface for the piston-rod, consists of relatively soft fibrous material adapted to contain lubricant. Adjoining this upon either side is a strip of relatively dense material such, for instance, as woven fabric with interposed layers of vulcanized indiarubber-and a backing-strip of resilient material, such as india-rubber. The relatively dense strips are preferably made smaller than the bearing-strip, so that as the latter is worn away the dense strips may be forced toward one another and press the bearing-strip against the piston-rod.

Sectional packing composed of triangular strips has heretofore been used; but the arrangement of the component parts has been more or less objectionable and unsuccessful in practical use.

By my improved construction I obtain the desirable soft bearing-surface with contained lubricant supported upon either side by a firm substantially incompressible strip and these backed by a resilient strip to give yielding pressure upon the soft bearing-strip communicated through its firm side supports.

Referring to the drawing, B is the strip of relatively soft fibrous material which bears upon the piston-rod and contains a lubricant. It is preferably made larger than the other strips, as shown. The supporting substantially incompressible side strips are designated I I and preferably are made small enough toprevent their apexes from meeting when first put to use.

R is the resilient backingstrip, and C the enveloping covering for the whole.

A portion of a piston-rod is indicated by dotted lines.

I claim- A steam-packing embodying four triangular strips arranged with their apexes toward its center, whereof the bearing-strip consists of relatively soft fibrous material adapted to contain lubricant, two adjoining side strips of relatively dense material, such as woven fabric and india-rubber, and a backing-strip of resilient material, such as india-rubber.

ARTHUR W. CHESTERTON.

Witnesses:

R. L. RoBuR'rs, F. A. OoLLINs. 

